Interfacial tension because hydrophobic tails stick out of the solution and

Interfacial tension because hydrophobic tails stick

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Interfacial tension because hydrophobic tails stick out of the solution and break up the interactions with the air above the surface of the solutionoMicelles form when the interfacial layer becomes saturated & surfactant molecules aggregateThese are predictable because drug will form micelles the same way every timeImportant for biotechnologyoProblem: unpredictable about whether it’ll work in practiceOne of the last choicesoProblem: drug may form a micelle and sit within the coreMicelle has to break apart to release the drugCauses interpatient variabilityFood also affects releaseoMost common surfactant = Tween 80 (polysorbate 80)HLB value of 14 Water-loving & good solubilizerCommon oral liquid vehicles
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-Elixir – hydroalcoholic mixture with some type of smell infused & ready to go-Simple syrupopH is on the acidic side due to sugaroSyrup – oral solutions containing a high concentration of sugar or other sugarsoSelf-preservativeOnly happens when there are very small amounts of free waterWhen you dilute it, the preservative factor goes away-Ora-Sweet & Ora-Sweet SF are widely usedoBoth purposely adjusted to acidic pHoContains its own excipients that give it its propertiesi.e. viscosity enhancers, crystallization preventer, buffer, antioxidant & preservative, flavoring, & sweeteningExcipients used in oral pharmaceutical solutions-Co-solvents-Buffers-Surfactants-Sweetening agentsoOrganoleptic propertyoMake unpleasant taste of an active drugoCan be natural (i.e. sucrose, sorbitol, mannitol) OR artificial (i.e. saccharine, aspartame)Sucrose should be avoided in high amounts with diabetic patientsAlso should be avoided in patients suffering from hereditary fructose intoleranceChronic use can result in cavities or other dental issuesNon-sucrose syrups include dextrose & sorbitolSorbitol is limited to 70% due to laxative propertiesPreservatives are requiredoOther diabetic syrupsCan make a sugar free syrup with just drug & buffer but should add a viscosity agent as wellMethylcellulse, hydroxyethylcellulose, sodium carboxymethylcelluloseCan add sugar-free sweeteners as wellAspartame (150-200x as sweet as sucrose)oPROBLEM: harmful to people with phenylketonuria-Flavoring agentsoOrganoleptic propertyoImprove palatability & patient acceptanceOften for pediatric solutionsoFlavor preference is very subjective & somewhat age-relatedoMasking flavorsSalty – apricot, butterscotch, liquorice, peach, vanillaBitter – anise, chocolate, mint, passion fruit, wild cherrySweet – vanilla, fruit, berriesSour – citrus fruits, liquorice, raspberry-Coloring agentsoOrganoleptic propertyoMake the product more attractiveUsually chosen to be associated with the flavoroFall into the following groups:
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Azo dyes – tartrazine, sunset yellowQuinolone dyes – quinolone yellowTriphenylmethane dyes – FDC&C blueoHave been associated with hypersensitivity & other adverse reactions-PreservativesoRetard microbial grownoShould be:Compatible with the rest of the formulation & the container
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